During his junior year studying mechanical engineering at the Massachusetts Institute of Technology (MIT), Benjamin Harvatine sustained a serious wallop to his head while competing in a wrestling match. He is not sure exactly when, during that fateful match, he sustained this concussion, but he recalls thinking, "Just keep pushing." Following the match, he realized he was more than just fatigued—he was also dizzy and had trouble speaking clearly. Throughout the months it took Harvatine to fully recover, he was dogged by the question: How could this have been prevented? Then, while enrolled in a class called Sensors & Instrumentation, he realized how he could have avoided that concussion—and he also saw a business opportunity to innovate the ways in which young athletes and their coaches track and evaluate concussions, by using a combination of wireless sensors and a smartphone application.

"We had a project called 'Go Forth & Measure,'" Harvatine says. The assignment was to select sensors from a wide array of options, take them out into the real world, measure something and report back through a poster session. "So I took a couple accelerometers and strapped them all over my wrestling headgear."

The Jolt sensor is clipped to a soccer player's headband.

During the past few years, physicians, athletes and coaches have become increasingly aware of the dangers and prevalence of sports-related concussions. Such brain injuries disrupt synaptic connections and can have long-term health effects, especially on youth athletes whose brains are still developing. According to the New Jersey-based nonprofit group Cleared to Play, 21 percent of all traumatic brain injuries among children in the United States are associated with participation in sports and recreational activities. Even soccer headers (passing the ball with one's head) can lead to serious injury, depending on the frequency and intensity of impact. The New York Times recently reported on a study showing that a history of multiple head injuries seemed to increase the likelihood of developing amyotrophic lateral sclerosis (ALS).

Wrestling headgear consists of ear guards that cover a competitor's ears to protect them from an injury commonly known as "cauliflower ear" that is caused by repetitive impacts. Such headgear, however, offers no protection from blows that could lead to a concussion. With the sensors attached, Harvatine was able to record the number and severity of knocks that he sustained to the head in the course of a match—information that could be used to determine in the event that an athlete was approaching an injury-inducing threshold.

Buoyed by his initial results, Harvatine began asking teammates to try out the very rudimentary and not-yet-wireless setup he had devised. "I had to follow people around the mat," he recalls with a chuckle, "because the sensors were tethered to a data logger that was plugged into my laptop." For the class, which took place during April 2011, he developed a proof-of-concept prototype wired sensor, designed to track and log dangerous head impacts.

Harvatine then began fleshing out the idea further with Seth Berg, a former MIT classmate and electrical engineer. The sensor would need to collect impact data over time, Harvatine explains, and transmit that information wirelessly to a smartphone application, which would analyze the raw data so that coaches, players, trainers and parents could then make sound decisions regarding whether players should take a break and allow time for healing. When athletes continue training while recovering from a concussion, secondary brain injuries can have serious, long-term consequences. To help detect significant head impacts and determine whether they merit extended rest time for recovery, the app also offers short cognitive tests that athletes can undergo on the sidelines and then upload for coaches to review. The full solution—consisting of the sensor and phone app—is called Jolt. The pair launched a Kickstarter campaign in late August to fund the project, and are now 50 percent of the way toward achieving their $60,000 goal.